By my opinion you are talking about the same. What is a fairness? For me situation when both part will get maximum of outcome from negotiation is rather fair. The problem is that this is just my opinion :-) Let me explain.
Let's imagine abstract negotiations involving two people (Mr. A and Mr.B). Following completion of negotiations, each party will receive abstract valuable points.
Let's assume, that there are 3 possible finals:
- 1) Mr. A: 5, Mr.B:5
- 2) Mr. A:10, Mr.B:4
- 3) Mr. A:3 or Mr.B:8.
First, let look at these possible finals in the context of "fairness". What of whese finals we can call "fair"?
Mr. A may think that result of first final is not fair, because in second final he will get five times more, than Mr. B will lose. Mr. B may think the same (but he will compare result with third final).
And, obviously, Mr. A and Mr. B will will not call "fairness" third and second finals, respectively.
Outside observer may think that second result is most "fair", because in that case total outcome is biggest.
Who of them are right? I don't know.
Now, let look at these possible finals in the context of "maximum outcome for both part".
It's easy. Only first result satisfy this constraint.
So, problems of win-win negotiations is that assumed that all people have the same objective definition of fairness. I am a subjectivist and I think that fairness has no objective definition at all. On the other hand "Maximum outcome for both part" have no this problems.